But, what about the kind of monster some people speculate could actually exist. This week, we offer medical insight about a potential zombie apocalypse.

The idea of a widespread outbreak of an illness that can transform people into zombies is a pop culture phenomenon that fascinates people. But, could it actually happen?

There are plenty of types of opportunistic pathogens that could potentially make zombies out of us. Brain parasites, for one, could transform the way a person thinks and increase irrational behavior, while not impacting life-preserving processes in the human body. A slight variation in some of the known parasites could potentially create a condition similar to zombies.

Infections like Creutzfeldt-Jakob disease, what we call Mad Cow disease in humans, could also potentially change a significant portion of the population if a widespread outbreak were to occur. Symptoms include confusion, dementia, hallucinations and significant personality changes. Luckily, livestock are now closely monitored to avoid the transmission of this disease to humans, so infection is rare.

If those two examples of how a zombie apocalypse could theoretically happen have gotten you scared, don’t worry. There are plenty more reasons why an outbreak like this is unlikely. Zombies, in their traditional sense, would have many natural predators, from large animals to parasites, and those would quickly unravel the undead. Furthermore, they would have little resistance to the elements. Finally, biting, traditionally considered the main means by which zombies spread infection, is not as effective as say, an airborne illness.

Our fear of zombies may actually be related to our general fear of widespread pandemics. And the best defense against that is to wash hands, practice good hygiene and be careful around folks who are sick. So make sure to practice safety this Halloween for your family’s fun.